"I have a better idea," Tench said, her barren eyes finding his. "Let me take the spot myself."

Zach Herney's head shot up. "You?" What the hell is she thinking? "Marjorie, you don't do media spots. Besides, it's a midday cable show. If I send my senior adviser, what kind of message does that send? It makes us look like we're panicking."

"Exactly."

Herney studied her. Whatever convoluted scheme Tench was hatching, there was no way in hell Herney would permit her to appear on CNN. Anyone who had ever laid eyes on Marjorie Tench knew there was a reason she worked behind the scenes. Tench was a frightful-looking woman-not the kind of face a President wanted delivering the White House message.

"I am taking this CNN debate," she repeated. This time she was not asking.

"Marjorie," the President maneuvered, feeling uneasy now, "Sexton's campaign will obviously claim your presence on CNN is proof the White House is running scared. Sending out our big guns early makes us look desperate."

The woman gave a quiet nod and lit a cigarette. "The more desperate we look, the better."

For the next sixty seconds, Marjorie Tench outlined why the President would be sending her to the CNN debate instead of some lowly campaign staffer. When Tench was finished, the President could only stare in amazement.

Once again, Marjorie Tench had proven herself a political genius.

The Milne Ice Shelf is the largest solid ice floe in the Northern Hemisphere. Located above the Eighty-second Parallel on the northernmost coast of Ellesmere Island in the high Arctic, the Milne Ice Shelf is four miles wide and reaches thicknesses of over three hundred feet.

Now, as Rachel climbed into the Plexiglas enclosure atop the ice tractor, she was grateful for the extra parka and gloves waiting for her on her seat, as well as the heat pouring out of the tractor's vents. Outside, on the ice runway, the F-14's engines roared, and the plane began taxiing away.

Rachel looked up in alarm. "He's leaving?"

Her new host climbed into the tractor, nodding. "Only science personnel and immediate NASA support team members are allowed on-site."

As the F-14 tore off into the sunless sky, Rachel felt suddenly marooned.

"We'll be taking the IceRover from here," the man said. "The administrator is waiting."

Rachel gazed out at the silvery path of ice before them and tried to imagine what the hell the administrator of NASA was doing up here.

"Hold on," the NASA man shouted, working some levers. With a grinding growl, the machine rotated ninety degrees in place like a treaded army tank. It was now facing the high wall of a snow berm.

Rachel looked at the steep incline and felt a ripple of fear. Surely he doesn't intend to-

"Rock and roll!" The driver popped the clutch, and the craft accelerated directly toward the slope. Rachel let out a muffled cry and held on. As they hit the incline, the spiked treads tore into the snow, and the contraption began to climb. Rachel was certain they would tip over backward, but the cabin remained surprisingly horizontal as the treads clawed up the slope. When the huge machine heaved up onto the crest of the berm, the driver brought it to a stop and beamed at his white-knuckled passenger. "Try that in an SUV! We took the shock-system design from the Mars Pathfinder and popped it on this baby! Worked like a charm."

Rachel gave a wan nod. "Neat."

Sitting now atop the snow berm, Rachel looked out at the inconceivable view. One more large berm stood before them, and then the undulations stopped abruptly. Beyond, the ice smoothed into a glistening expanse that was inclined ever so slightly. The moonlit sheet of ice stretched out into the distance, where it eventually narrowed and snaked up into the mountains.

"That's the Milne Glacier," the driver said, pointing up into the mountains. "Starts up there and flows down into this wide delta that we're sitting on now."

The driver gunned the engine again, and Rachel held on as the craft accelerated down the steep face. At the bottom, they clawed across another ice river and rocketed up the next berm. Mounting the crest and quickly skimming down the far side, they slid out onto a smooth sheet of ice and started crunching across the glacier.

"How far?" Rachel saw nothing but ice in front of them.

"About two miles ahead."

Rachel thought it seemed far. The wind outside pounded the IceRover in relentless gusts, rattling the Plexiglas as if trying to hurl them back toward the sea.

"That's the katabatic wind," the driver yelled. "Get used to it!" He explained that this area had a permanent offshore gale called the katabatic-Greek for flowing downhill. The relentless wind was apparently the product of heavy, cold air "flowing" down the glacial face like a raging river downhill. "This is the only place on earth," the driver added, laughing, "where hell actually freezes over!"

Several minutes later, Rachel began to see a hazy shape in the distance in front of them-the silhouette of an enormous white dome emerging from the ice. Rachel rubbed her eyes. What in the world…?

"Big Eskimos up here, eh?" the man joked.

Rachel tried to make sense of the structure. It looked like a scaled-down Houston Astrodome.

"NASA put it up a week and a half ago," he said. "Multistage inflatable plexipolysorbate. Inflate the pieces, affix them to one another, connect the whole thing to the ice with pitons and wires. Looks like an enclosed big top tent, but it's actually the NASA prototype for the portable habitat we hope to use on Mars someday. We call it a 'habisphere.'"

"Habisphere?"

"Yeah, get it? Because it's not a whole sphere, it's only habi-sphere."

Rachel smiled and stared out at the bizarre building now looming closer on the glacial plain. "And because NASA hasn't gone to Mars yet, you guys decided to have a big sleepover out here instead?"

The man laughed. "Actually, I would have preferred Tahiti, but fate pretty much decided the location."

Rachel gazed uncertainly up at the edifice. The off-white shell was a ghostly contour against a dark sky. As the IceRover neared the structure, it ground to a stop at a small door on the side of the dome, which was now opening. Light from inside spilled out onto the snow. A figure stepped out. He was a bulky giant wearing a black fleece pullover that amplified his size and made him look like a bear. He moved toward the IceRover.

Rachel had no doubt who the huge man was: Lawrence Ekstrom, administrator of NASA.

The driver gave a solacing grin. "Don't let his size fool you. The guy's a pussycat."

More like a tiger, Rachel thought, well acquainted with Ekstrom's reputation for biting the heads off those who stood in the way of his dreams.

When Rachel climbed down from the IceRover, the wind almost blew her over. She wrapped the coat around herself and moved toward the dome.

The NASA administrator met her halfway, extending a huge gloved paw. "Ms. Sexton. Thank you for coming."

Rachel nodded uncertainly and shouted over the howling wind. "Frankly, sir, I'm not sure I had much choice."

A thousand meters farther up the glacier, Delta-One gazed through infrared binoculars and watched as the administrator of NASA ushered Rachel Sexton into the dome.